Abstract. A parameterization for the motion of ice-shelf fronts on a Cartesian
grid in finite-difference land-ice models is presented. The scheme
prevents artificial thinning of the ice shelf at its edge, which
occurs due to the finite resolution of the model. The intuitive
numerical implementation diminishes numerical dispersion at the ice
front and enables the application of physical boundary conditions to
improve the calculation of stress and velocity fields throughout the
ice-sheet-shelf system. Numerical properties of this subgrid
modification are assessed in the Potsdam Parallel Ice Sheet Model
(PISM-PIK) for different geometries in one and two horizontal
dimensions and are verified against an analytical solution in a
flow-line setup.